Distribution of Gulf of Mexico Sturgeon in Relation to Benthic Invertebrate Prey Resources and Environmental Parameters in the Suwannee River Estuary, Florida

2005 ◽  
Vol 134 (4) ◽  
pp. 975-990 ◽  
Author(s):  
Julianne E. Harris ◽  
Daryl C. Parkyn ◽  
Debra J. Murie
2021 ◽  
Vol 12 ◽  
Author(s):  
Cristina Bacian ◽  
Cristobal Verdugo ◽  
Katherine García ◽  
Josu Perez-Larruscain ◽  
Ignacio de Blas ◽  
...  

Vibrio parahaemolyticus is the leading cause of seafood-associated bacterial gastroenteritis worldwide. Although different studies have focused on its pattern of variation over time, knowledge about the environmental factors driving the dynamics of this pathogen, within the Chilean territory, is still lacking. This study determined the prevalence of total and pathogenic V. parahaemolyticus strains (tdh and/or trh genes) in mussels (Mytilus chilensis) collected from two natural growing areas between 2017 and 2018, using selective agar and PCR analysis. V. parahaemolyticus was detected in 45.6% (93/204) of pooled samples from the Valdivia River Estuary. The pathogenic strains carrying the tdh and/or trh gene were detected in 11.8% (24/204): tdh in 9.8% (20/204), trh in 0.5% (1/204), and 1.5% (3/204) presented both genes. In Reloncaví Fjord, V. parahaemolyticus was detected in 14.4% (30/209) of the samples, pathogenic V. parahaemolyticus carrying the trh gene was detected in 0.5% (1/209) of the samples, while the tdh gene was not detected in the samples from this area. The total count of mauve-purple colonies typical of V. parahaemolyticus on CHROMagar was positively associated by multivariate analysis with area, water temperature, and salinity. Similarly, V. parahaemolyticus detection rates by PCR had a positive correlation with the area and water temperature. The chances of detecting total V. parahaemolyticus in the Valdivia River Estuary are significantly higher than in the Reloncaví Fjord, but inversely, during spring-summer months, the interaction factor between the area and temperature indicated that the chances of detecting V. parahaemolyticus are higher in the Reloncaví Fjord. Interestingly, this period coincides with the season when commercial and natural-growing shellfish are harvested. On the other hand, pathogenic V. parahaemolyticus tdh+ was significantly correlated with an increase of water temperature. These environmental parameters could be used to trigger a warning on potential hazard, which would influence human health and economic losses in aquaculture systems.


2020 ◽  
Vol 8 (8) ◽  
pp. 608
Author(s):  
Jasna Arapov ◽  
Mia Bužančić ◽  
Sanda Skejić ◽  
Jelena Mandić ◽  
Ana Bakrač ◽  
...  

The Krka River estuary is a karstic, permanently stratified estuary due to the strong freshwater inflow. It is a special environment in which to study the phytoplankton community, especially because this area is an important aquaculture site. Among other potentially toxic phytoplankton species, the diatom genus Pseudo-nitzschia occurs frequently and is a potential source of domoic acid (DA), causing shellfish toxicity and human intoxication. The main objective was to examine the dynamics of the phytoplankton community and, in particular, the genus Pseudo-nitzschia in the upper part of the Krka estuary, through monthly sampling over two years. The phytoplankton community was analysed using light microscopy and scanning electron microscopy to determine the diversity of Pseudo-nitzschia species and characterise the environmental parameters associated with a high abundance of Pseudo-nitzschia species. Seven Pseudo-nitzschia species were identified in the investigation, with higher frequencies and abundances in the less variable layer, at a 7 m depth. Blooms of Pseudo-nitzschia were noted in the late summer/early autumn, dominated by P. delicatissima/arenysensis. Winter assemblages were characterised by P. pseudodelicatissima/cuspidata, P. calliantha, and P. subfraudulenta, and were associated with domoic acid occurrence in shellfish.


Hydrobiologia ◽  
2009 ◽  
Vol 632 (1) ◽  
pp. 127-137 ◽  
Author(s):  
Erin L. Quinlan ◽  
Christina H. Jett ◽  
Edward J. Phlips

Zoosymposia ◽  
2014 ◽  
Vol 9 (1) ◽  
pp. 70-76
Author(s):  
NAIME ARSLAN ◽  
DENIZ KARA ◽  
CANSEV AKKAN KÖKÇÜ ◽  
MELIH RÜZGAR

Çatören and Kunduzlar Dam Lakes, located on Seydi River, represent the main irrigation water resources of the Seyitgazi District (Eskişehir Province), in west-central Turkey. The river and the reservoirs are both under the threat of pollution primarily originating from several domestic point source discharges and land-based runoff. The numerical and proportional distributions of oligochaetes in Çatören and Kunduzlar Dam Lakes were surveyed seasonally in 2010 and 2011 at two stations on each lake. According to the results of this study, the benthic invertebrate fauna of Çatören Dam Lake consisted of Oligochaeta (40.2 %), Chironomidae larvae (32.2 %) and the varia (27.6 %); the benthic invertebrate fauna of Kunduzlar Dam Lake consisted of Oligochaeta (56.7 %), Chironomidae larvae (18.2 %) and the varia (25.1%). By evaluating the data via a Shannon-Wiener index it was found that the Çatören Dam Lake had an index of 2.32; while Kunduzlar Dam Lake had an index of 3.27. Several physicochemical water quality parameters were also analyzed during this study. The relationships between the dynamics of organisms and environmental parameters were supported by Pearson correlation index. It was determined that Çatören and Kunduzlar Dam Lakes waters were polluted and slightly polluted, respectively. The dominance and abundance of oligochaete species and low species richness showed that similar studies should be carried out periodically in Çatören and Kunduzlar Dam Lakes for the future monitoring of the dam lakes.


Author(s):  
Lenka Kajgrova ◽  
Zdenek Adamek ◽  
Jan Regenda ◽  
Christian Bauer ◽  
Vlastimil Stejskal ◽  
...  

Qualitative and quantitative differences in benthic macrozoobenthos distribution in carp pond littoral zones (macrophyte areas; LM) and pelagic zones (macrophyte-free areas; MF) were assessed in four commercial carp (Cyprinus carpio) grow-out ponds in the Czech Republic (semi-intensive management) and Austria (organic management) monthly over the growing season (June-September) of 2016 and 2017. While differences in environmental parameters and granulometric composition between LM and MF were statistically non-significant (p > 0.05), organic matter content was significantly higher (p < 0.05) in LM. Average macrozoobenthos density and biomass in LM (mean 431 ind.m−2 and 6.78 g.m−2) was usually significantly higher (p > 0.05) than MF (371 ind.m−2 and 3.17 g.m−2). A similar trend was observed for zoobenthos diversity, with LM having a higher diversity (76 taxa) than MF (47 taxa). At the start of the growing season, chironomid density was higher (p < 0.05) in muddy MF zones, regardless of management type, while oligochaete density was higher in muddy LM. The density of both groups later declined, such that density was significantly higher (p > 0.05) in sandy substrates, regardless of habitat or management type. Our data suggest a significant drop in macrozoobenthos density and biomass compared with historical data, mainly due to new management techniques (fertilisation, supplementary feeding) and intensification (higher stock densities), suggesting that pond management is crucial as regards benthic invertebrate development and diversity. Our results indicate that emersed LM beds positively influence macrozoobenthos performance in carp ponds, potentially making them biodiversity hotspots. Further, LM beds can be regarded as invertebrate harbours, and hence should be protected and encouraged.


Author(s):  
Dubravko Justić ◽  
Villy Kourafalou ◽  
Giulio Mariotti ◽  
Songjie He ◽  
Robert Weisberg ◽  
...  

AbstractEstuarine and coastal geomorphology, biogeochemistry, water quality, and coastal food webs in river-dominated shelves of the Gulf of Mexico (GoM) are modulated by transport processes associated with river inputs, winds, waves, tides, and deep-ocean/continental shelf interactions. For instance, transport processes control the fate of river-borne sediments, which in turn affect coastal land loss. Similarly, transport of freshwater, nutrients, and carbon control the dynamics of eutrophication, hypoxia, harmful algal blooms, and coastal acidification. Further, freshwater inflow transports pesticides, herbicides, heavy metals, and oil into receiving estuaries and coastal systems. Lastly, transport processes along the continuum from the rivers and estuaries to coastal and shelf areas and adjacent open ocean (abbreviated herein as “river-estuary-shelf-ocean”) regulate the movements of organisms, including the spatial distributions of individuals and the exchange of genetic information between distinct subpopulations. The Gulf of Mexico Research Initiative (GoMRI) provided unprecedented opportunities to study transport processes along the river-estuary-shelf-ocean continuum in the GoM. The understanding of transport at multiple spatial and temporal scales in this topographically and dynamically complex marginal sea was improved, allowing for more accurate forecasting of the fate of oil and other constituents. For this review, we focus on five specific transport themes: (i) wetland, estuary, and shelf exchanges; (ii) river-estuary coupling; (iii) nearshore and inlet processes; (iv) open ocean transport processes; and (v) river-induced fronts and cross-basin transport. We then discuss the relevancy of GoMRI findings on the transport processes for ecological connectivity and oil transport and fate. We also examine the implications of new findings for informing the response to future oil spills, and the management of coastal resources and ecosystems. Lastly, we summarize the research gaps identified in the many studies and offer recommendations for continuing the momentum of the research provided by the GoMRI effort. A number of uncertainties were identified that occurred in multiple settings. These include the quantification of sediment, carbon, dissolved gasses and nutrient fluxes during storms, consistent specification of the various external forcings used in analyses, methods for smooth integration of multiscale advection mechanisms across different flow regimes, dynamic coupling of the atmosphere with sub-mesoscale and mesoscale phenomena, and methods for simulating finer-scale dynamics over long time periods. Addressing these uncertainties would allow the scientific community to be better prepared to predict the fate of hydrocarbons and their impacts to the coastal ocean, rivers, and marshes in the event of another spill in the GoM.


2010 ◽  
Vol 82 (3) ◽  
pp. 577-583 ◽  
Author(s):  
Natália R. Leite ◽  
Luci C.C. Pereira ◽  
Fernando Abrunhosa ◽  
Marcus A.B. Pires ◽  
Rauquírio M. da Costa

The present work was carried out to verify the occurrence and distribution of Cymbasoma longispinosum Bourne, 1890 in a tropical Amazon estuary from North Brazil. Samplings were performed bimonthly from July/2003 to July/2004 at two different transects (Muriá and Curuçá rivers) situated along the Curuçá estuary (Pará, North Brazil). Samples were collected during neap tides via gentle (1 to 1.5 knots) 200 μm-mesh net tows from a small boat. Additional subsurface water samples were collected for the determination of environmental parameters. Males and females of Cymbasoma longispinosum were only observed during September and November/2003. The highest number of organisms was found in September/2003 at the Muriá River transect. The presence of C. longispinosum in samples obtained during September and November/2003 could probably be related to the reproductive period of this species in the studied estuary, which is directly related to the dry period in the region. The highest salinity values and the highest number of individuals observed in September/2003 corroborate with the previous assumption, since no C. longispinosum was found during the months comprising the rainy period (January to June).


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